LAGOS, Nigeria – Amnesty International says it has evidence hundreds of people are dying in detention as the military cracks down on an Islamic uprising in northeast Nigeria.

The London-based rights group in a report Tuesday said that "credible information" from a senior Nigerian army officer indicates more than 950 people died in military custody in the first six months of this year.

It says senior Ministry of Defense officials have not responded to written details about soldiers on April 19 depositing 60 bodies at the main hospital mortuary in Damaturu, the Yobe state capital, claiming they were killed in a shootout. But a source told Amnesty they were detainees taken from their cells and shot.

It said other detainees have suffocated and starved to death in horrendous conditions.

Nigeria's military is notorious for extrajudicial killings of civilians.